1. Field
The present disclosure relates to methods of producing an unsaturated acid from a salt of a hydroxycarboxylic acid.
2. Description of the Related Art
Hydroxycarboxylic acids produced via fermentation may be useful in an industrial process of various purposes, such as synthesizing polyester or polyamide. However, in order to increase productivity of a fermentation process, a neutralizing agent, such as ammonia or calcium hydroxide, needs to be added to neutralize acid produced from the fermentation.
Additionally, in order to collect a hydroxycarboxylic acid present in the fermentation product, a mineral acid, such as sulfuric acid, is conventionally added to the product to perform acid-treatment, and thus ammonium sulfate or gypsum (calcium sulfate) is produced as a by-product.
Thus an additional process and facility for implementing said process are needed to purify fermentation by-products and convert hydroxycarboxylic acid into unsaturated carboxylic acid. Such additional processes raise production costs in part because additional waste generated from the additional process needs to be removed as well.
Therefore, an efficient salt splitting process is needed to effectively use hydroxycarboxylic acid salts in industrial fermentation processes.